Ceramic flux



UNITED STATES PATENT OFFICE V I salmon b No Drawing. Application April 16, 1938, Serial No. 202,512

1 Claim. (01. 100-11) Thisinvention relates generallyto an improveural, volcanic rhyolitic tuff (a light grey sediment in the manufacture of vitrified ceramic mentary rock) including, by analysis of a typical products, and in particular theinvention is dispecimen, the following constituents and in the rected to an improved ceramic flux and the manfollowing proportions:

5 ner of its use. Per cent 5 At the present time the most commonly used 5m 310, 68,90 ceramic flux is powdered feldspar a d it is used Alumina, (Ala O "1531a extensively in combination with clay to produce Titania (T102) 23 vitrified ware. However, when p wd feld- Ferric oxide (FezOg) 2.54

spar is used as the flux, the P od c must be fired Manganese oxide (M11360 0.10 m at a temperature not less than cone 9 (2282 F. Lime c o 230 or 1250" c.) in order to effect proper fus -Magnsia (MgO) 1.72 It is the principal object of the present inven- Loss on Ignition 4.14 tion to provide a ceramic flux which, when used Moisture Q46 in proper proportion with clay, will fuse and Alkanes (K20, N840) by dmerence 333 15 vitrify fully at cone 4 (2093 F. or 1145" C.) when quick fired, or cone 3 (2129. R 0 Q) m V The tuif, after mining thereof, is prepared for slow commercial firing. This results in substanuse by first grinding by means of suitable equip a! saving in time and arms, csts ment to a dry, granular, er in the presence of It is also my purpose to provide a ceramic flux water, to a wet, plastic form. Thereafter, if 20 which, while roducm er vitrification at desired, it is subjected to a magnetic separator a relatively tempergtuge' a range to cone in order to remove all the iron content which is 26 (approximately 3000 F.) which is its melting undesirable if the flux is to be used m the making point In other words, my improved flux has of certain wares, other than colored ware, where the particles of iron would be noticeable. ts h g zg g gzs g g ga fig elemen m t 8 After preparation as above, the fiux, either in dry or wet form, is employed much in the same Furth ami flux advantages of my improved oer c manner as other ceramic fluxes. It is included in a mix with fire clay or other body .plasticizer;

(a) Produces a dense, heavy, and waterproof th rm f n d :0 product having low absorption characteristics. propo on o use apparently is 30 (b) The flux is sharp and'therefore holds the critical and preferably not less than 10% and ranging upwardly in proportion-depending of 3 2:; better when applied to the ware before course on the characteristics of the fire clay in shin the mix, and kind of ware desired, cost, etc. {0) The flux bums bright and y whereas Products prepared from such mix are formed,

certain other fluxes burn dark and dull, and there is lime if any drying shrinkage and no more dried, and fired in the usual manner and in ac- 35 than the usual b i g l kasa cordance with standard potters practice, except (a) While the flux vltrifiesat a relatively low that the firing temperature need 3 temperature, it maintains the product configura- 2; produce fullyd fusedboand fi ware 40 tion without distortion when fired to a relatively hard and ense d dy w ch is qtnte 40 high heat. This is due to sufllcient silica content as well as proof and whlch in the flux due to its hardness, will support a glaze and (e) The flux due to its crystalline form and reduce the tendency of the glaze to chip off as little or no drying shrinkage, facilitates the dryg i gggfiggg gfgg 2f; ing of a plastic mass, in which it is incorporated, manufacture of all types of vitrified ware such 45 and without warping or cracking of the product.

A further object of my invention is to provide as pottery, floor tile, etc., and distortion is rea ceramic flux which will be exceedingly effective duced to minimum The ,other advantages of f the purpose for which it intended to be such fiux have heretofore been set forth in this used. specification. 50

These objects 1 acgompllsh 1 t manner as From the foregoing description it will be readwill fully appear by a, perusal oft following ily seen that I provide a ceramic flux which subspecification and claim. stantially fulfills the objects of the invention as Referring now in particular to my improved set forth herein. ceramic flux, the material which I use is a nat- While this specification sets forth the present 55 A mix adapted for the manufacture of vit rified ware, said mix including fire clay and a ceramic flux; said flux including, in substantially the following proportions, 68.90% silica, 15.78% alumina, 0.28% titania, 2.54% ferric oxide, 0.10% manganese oxide, 2.80% lime, 1.72% magnesia and 3.28% alkalis.

DANA A. CANNON. 

